A biocontrol strain designated LS06 was isolated and purified from the rhizosphere soil of diseased tobacco plants using the dilution plating method. The biocontrol potential of strain LS06 was evaluated through dual culture assays, 16S rRNA gene sequencing and alignment, genome sequencing analysis, and pot experiments. Dual culture assays showed that strain LS06 inhibited seven Fusarium species, with inhibition rates ranging from 36.69% to 49.30%. The strain LS06 was identified as Brevibacillus brevis, with a genome size of 6 131 499 bp. COG annotation indicated that it harbors 5 768 genes, of which 34 genes are associated with chemotaxis, motility, and siderophore synthesis. The genome contains 14 biosynthetic gene clusters(BGCs) for secondary metabolites. Four of these clusters exhibit more than 78% similarity to known BGCs, whereas the products of the remaining 10 clusters remain unknown, suggesting that strain LS06 possesses the potential to synthesize diverse antimicrobial compounds. Pot experiments demonstrated that the relative control efficacy of strain LS06 against the seven Fusarium species ranged from 64.74% to 76.74%. In conclusion, strain LS06 is capable of inhibiting seven major Fusarium species, has the potential to produce various antimicrobial substances, and shows considerable promise for application in the biological control of Fusarium root rot.